Catalytic wire gauzes have been used for many years for ammonia oxidation. The flow and transfer properties of stacked gauzes, however, have not been sufficiently examined in the literature. This study presents an experimental program designed to characterize the pressure drops observed across stacked woven and knitted wire gauzes. This work generated an extensive database of measurements and reveals that each gauze requires its own correlation equation. Furthermore, previously published general models were not able to describe all four cases with high accuracy. After surveying the literature, we present some modifications to the models based on our collected experimental results.